passed in D0:D1. If the first argument is not a 64-bit value, but the second
is, the second will be passed entirely on the stack and D1 will be unused.
-Arguments smaller than 32-bits are not coelesced within a register or a stack
+Arguments smaller than 32-bits are not coalesced within a register or a stack
word. For example, two byte-sized arguments will always be passed in separate
registers or word-sized stack slots.